Featured Research

from universities, journals, and other organizations

'Middle Class' Coral Reef Fish Feel The Economic Squeeze

Date:

February 18, 2009

Source:

Wildlife Conservation Society

Summary:

The economy isn't just squeezing the middle class on land, it's also affecting fish. Overfishing on coral reefs isn't simply caused by too many people. Rather, researchers found that the biomass of fish found on coral reefs in the western Indian Ocean depended mostly on the complexity of the reefs themselves and the socioeconomic status of the people living on the shores.

Share This

According to a recent study by WCS and other organizations, coral reefs next to "middle class" communities in Eastern Africa have the lowest fish levels. In contrast, reefs next to villages of low and high socio-economic levels had higher fish levels.

Credit: Copyright Tim McClanahan

The economy isn't just squeezing the middle class on land, it's also affecting fish.

Related Articles

Wealthy areas and least developed regions have healthiest fish populations, while those in the middle are suffering

According to a study by the Wildlife Conservation Society (WCS) and other organizations, researchers discovered a surprising correlation between "middle class" communities in Eastern Africa and low fish levels. Curiously, areas with both low and high socio-economic levels had comparatively higher fish levels.

Appearing in the latest edition of Current Biology, the study examined reef systems, human population densities, and socio-economics among villages in 30 fished and unfished study sites in five countries along Africa's Indian Ocean coast.

The study is by Josh Cinner of James Cook University (JCU), Tim McClanahan of the Wildlife Conservation Society (WCS), Tim Daw of the University of East Anglia, Nick Graham of JCU, Joseph Maina of WCS, and Shaun Wilson and Terry Hughes of JCU.

In a comparison between villages, researchers found that communities with intermediate levels of infrastructure had the lowest fish levels in their adjacent reef systems—up to four times lower than sites of low and high levels of development.

"This is a significant finding on how socio-economics can influence reef fisheries in surprising ways," said Dr. Tim McClanahan, a WCS coral researcher and co-author of the study. "It also shows the importance of combining ecology with social science for conservation planning on a regional scale."

The explanation, said researchers, lies in the interplay between traditional customs and how growth influences the social fabric of communities. In poor communities, many of which rely heavily on marine resources, fishing levels are kept in check by local cultural institutions and taboos and a reliance on traditional, low-tech fishing methods. Increases in wealth often reduce a community's dependence on fishing, but it can also increase the number of motorized fishing vessels and fishing gear such as handlines.

Economic growth during the early stages can also erode cultural restrictions on overfishing, according to the authors. The net result: fewer fish. Among the countries studied, Kenya in particular, has experienced a sharp decline in cultural restraints and a subsequent increase in unrestrained and destructive fishing techniques.

The most affluent communities, by contrast, become less dependent on marine resources and more diversified economically, with more salaried positions and economic opportunities. Wealthier communities also possess higher levels of technology—larger boats that enable fishermen to fish on the open sea—and an increased awareness on the importance of coral reefs on ecological health.

The U-shaped curve in fish biomass with respect to socioeconomic levels approximates what is known as an environmental "Kuznet curve," which is adapted from a graphical model that measures economic inequalities in developing countries driven by the extent of a countries economic influence.

Predictably, the research also found that fish levels were always negatively but not strongly affected by high human population density. And protected marine sites with no fishing had fish levels three times higher than sites where fishing was permitted.

"Coral reef fishery management will depend not just on fishing laws but also on improving human welfare and institutional capacity through appropriate socioeconomic development" added McClanahan. "Governments, donors, and other agencies help communities avoid 'poverty traps' through investments in programs and alternatives to reef-based livelihoods, where obvious examples include infrastructure developments such as schools and hospitals."

Mar. 31, 2015 — Using the assessment tool ForWarn, US Forest Service researchers can monitor the growth and development of vegetation that signals winter's end and the awakening of a new growing season. Now these ... full story

Mar. 31, 2015 — Until now electric fences and trenches have proved to be the most effective way of protecting farms and villages from night time raids by hungry elephants. But researchers think they may have come up ... full story

Mar. 31, 2015 — Researchers have detected a human fingerprint deep in the Borneo rainforest in Southeast Asia. Cold winds blowing from the north carry industrial pollutants from East Asia to the equator, with ... full story

Mar. 31, 2015 — A team of engineers and biologists reports new progress in using computer modeling and 3D shape analysis to understand how the unique grasping tails of seahorses evolved. These prehensile tails ... full story

Mar. 31, 2015 — As the five-year anniversary of the explosion of the Deepwater Horizon oil rig approaches, a new report looks at how twenty species of wildlife are faring in the aftermath of the ... full story

Mar. 31, 2015 — Scientists have uncovered the earliest fossilized evidence of an insect caring for its young. The findings push back the earliest direct evidence of insect brood care by more than 50 million years, ... full story

Mar. 31, 2015 — New research has scientists re-thinking how a lethal fungus grows and kills immune cells. The study hints at a new approach to therapy for Candida albicans, one of the most common causes of ... full story

Mar. 31, 2015 — The most virulent strains of Streptococcus suis, the leading cause of bacterial meningitis in adult humans in parts of southeast Asia and in pigs around the world, are likely to have evolved and ... full story

Mar. 31, 2015 — Darwin's evolutionary theory predicts survival of the fittest. So why do different survival tactics co-exist, if evolution should always favor the winning strategy? To answer that question scientists ... full story

Bionic Ants Could Be Tomorrow's Factory Workers

Reuters - Innovations Video Online (Mar. 30, 2015) — Industrious 3D printed bionic ants working together could toil in the factories of the future, says German technology company Festo. The robotic insects cooperate and coordinate their actions and movements to achieve a common aim. Amy Pollock reports.
Video provided by Reuters

Lions Make Surprise Comeback in Gabon

AFP (Mar. 30, 2015) — Lions have made a comeback in southeast Gabon, after disappearing for years, according to live footage from US wildlife organisation Panthera. Duration: 00:32
Video provided by AFP

Apr. 10, 2014 — The world's reefs are hotbeds of biological diversity, including over 4,500 species of fish. A new study shows that the ancestors of these fish colonized reefs in two distinct waves, before and ... full story

Feb. 23, 2011 — Semporna may have the world's highest marine biodiversity. A recent expedition yielded a record number of 43 species of mushroom corals. Furthermore, some new species were discovered, among ... full story

Feb. 15, 2011 — More than a third of coral reef fish species are in jeopardy of local extinction from the impacts of climate change on coral reefs, a new scientific study has found. A new predictive method developed ... full story

Feb. 14, 2011 — The more humanity acidifies and warms the world's oceans with carbon emissions, the harder we will have to work to save our coral reefs. That's the blunt message from a major new study ... full story

ScienceDaily features breaking news and videos about the latest discoveries in health, technology, the environment, and more -- from major news services and leading universities, scientific journals, and research organizations.